The purpose of this training program is to prepare M.D., M.D./Ph.D. postdoctoral fellows for research careers in the multi-disciplinary field of Transfusion Medicine (TM). Fellows will conduct independent research in the laboratory of an experienced mentor, selected among faculty with diverse interests including cell membrane (red blood cells, platelets) structure and function, immunobiology of autoimmune and neoplastic disorders, hematopoiesis and virology. The 13 mentors selected for this program include 10 senior scientists with extensive experience training both predoctoral and postdoctoral fellows, and with current, active, interlaboratory collaborations. The uniqueness of this training program lies in the availability of a broad-based research environment coupled with a well established clinical TM fellowship training program. This provides fellows with the opportunity to pursue focused research training or to incorporate clinical TM fellowship training depending upon their previous educational experience. During the first 4 years of training grant support (1994 to present), 9 fellows have successfully completed the program, some acquiring research funding (e.g. KO8) or establishing permanent positions with research responsibilities as TM junior faculty or research scientists.